Missing data in a logistic regression analysis

I am performing a logistic regression analysis with all my data dichotomized (0/1). My problem is that I have a lot of missing data and the analysis eliminates participants listwise (i.e., eliminates a participant even if they have only 1 missing at any variable).

I do not want to impute the missing data but I am wondering if the analysis could be run for different number of participants per variable. For instance, gender and bullying has 500 complete cases but nationality has 450 complete cases and 50 missing. If bullying is my dependent variable, gender comparisons would include 500 participants but nationality would include 450.

What do you think?

• You can fit pairwise models if you want to assess the impacts of the binary variables on your binary outcome, so (assuming Bullying  is your dependent variable) you can do Bullying~Gender, followed by Bullying~Nationality, etc. It seems like you do not have a lot of missingness though, so I would recommend that you try imputing and fitting a single model rather than n models where n is the number of predicitve features. – Zhubarb Jan 9 '18 at 11:58
• If you run your models on different subsets of the participants they will not be directly comparable and may even be mis-leading. Imputation is the way to go as @Berkmeister suggests – mdewey Jan 9 '18 at 12:03
• Thank you very much! Which imputation method would you recommend? If variables are dummy coded I would need to imput either 0 or 1. I believe I cannot imput based on mean, median, etc., right? Thank you again. – Izabela Jan 9 '18 at 12:34
• Modifying the old Latin proverb, "Every imputation is a liar". In order to protect against misleading results due to a particular imputation, I'd recommend multiple imputation. There's a nice program to do this called Amelia, and you can then combine the results with Zelig. See Gary King's page gking.harvard.edu/amelia . Because you have 0/1 dichotomies, see section 4.3.1 in the documentation r.iq.harvard.edu/docs/amelia/amelia.pdf – zbicyclist Jan 9 '18 at 14:09
• also see the mice R package – Ben Bolker Jan 10 '18 at 15:22